After 15 years of singing his songs in public, 39-year-old John Prine is writing some the best songs of his career, as revealed at Wolf Trap last night.

The clever romanticism of his early work has given way to a darker humor and a harder look at his characters from the fringes of American life. Performing alone with his acoustic guitar, Prine lent an off-handed dry drawl to songs like "Aimless Love" and "Linda Goes to Mars" that balanced an essential loneliness against a desperate urge to overcome it. Unfortunately, Prine suffered early on from the mumbles -- a fatal flaw for a songwriter who depends so much on his lyrics.

The Seldom Scene plays around here so often that it's easy to forget what a special band this all-star bluegrass quintet is. Last night's opening set was a welcome reminder.

One expected the consistently top-notch picking, especially from much-recorded dobroist Mike Aulridge and ever-restless bassist Tom Gray. It's less widely recognized that Phil Rosenthal is one of the most expressive singers in traditional country music. When Aulridge and John Duffey joined him for rich three-part harmonies on "Hickory Wind" and "I Know You Rider," the effect was all the more striking for being so nicely understated.